DISCLAIMER: The world of popular bodybuilding has always been and probably always will be full of exaggerations, deceptions and, sometimes, outright lies. Unfortunately, those exaggerations often shape people’s perceptions of bodybuilders’ legitimate measurements. The purpose of the information presented in this article is to provide accurate references and tools so people can form appropriate training expectations based on reality. That said, even many adults don’t have the maturity and intelligence to accept and deal with knowledge of their own limitations. If you’re comfortable with your current perception of your bodybuilding potential (depending on how realistic your training expectations are) and think that any threat to that perception might negatively influence your self-image or motivation to train then do not read this article.

“The truth is incontrovertible. Panic may resent it, ignorance may deride it, malice may distort it, but in the end, there it is.”
- Sir Winston Churchill

For a drug-free bodybuilder trying to develop maximum muscle mass, the knowledge of how much muscle can be developed without the use of anabolic drugs would be a very valuable asset. Unfortunately, because of the achievements of drug-using professional, amateur and recreational bodybuilders, many natural lifters either have no idea of their actual potentials, they over-estimate what they can realistically achieve or they adopt a defeatist attitude and set their goals too low. Perspective is needed. The ability to set ambitious, yet realistic, goals is needed. And while there is no doubt that through natural bodybuilding a trainee can develop truly impressive, strong muscles, the chances of a drug-free bodybuilder attaining lean 22″ arms are about the same as him sprouting wings.
Maximum muscular bodyweight and size potential are positively correlated with a person’s height and bone-structure [1-6]. Simply put, naturally large-structured men generally have the potential to develop larger muscles than slightly built men. Reflecting that, there are several formulae in popular use that predict a person’s maximum muscular weight based on these variables (with bone-structure size typically estimated by measuring the circumference of the wrist). Bodybuilding legend Steve Reeves presented simple formulas for calculating what he considered to be ideal muscular weight. He suggested starting with a base of 160 pounds and adding 5 pounds for every inch of height above 5’5″. For people above 6’0″, he suggested starting with 200 pounds and adding 10 pounds per inch. Using these formulae, a person 5’9″ would have an ideal muscular weight of 180 pounds. A person 6’1″ would weigh 210 pounds. The problem with these predictions is that they do not consider bone structure size.

In his book, Beyond Brawn, Stuart McRobert also proposed a method of estimating maximum muscular bodyweight. The suggestion is to start with 5’0″ as a base height and 100 pounds as a base weight. Then add 10 pounds for every inch of height above 5’0″ for a medium bone structure, 8 pounds for a small structure, and 12 pounds for a large structure. Above 5’9″ add only half those amounts. A person of 5’9″ with a medium structure would weigh 190 pounds. A person of 6’1″ with a large structure would weigh 232 pounds. This is a worthwhile refinement of the simple linear approach, but becomes inaccurate when dealing with very large and/or very small structured people.

In the scientific community, Dr. E. M. Kouri, et. al. presented a comparison between the lean body masses of drug-free vs. drug-using lifters based upon their fat-free mass indexes (FFMI) [7]. This formula can be solved for maximum lean body mass at a given height if a maximum FFMI is assumed for drug-free lifters. The problem with doing this, however, is that, again, bone structure is not considered – though the works of Cameron et al. and Glauber et al. indicate clearly that such a relation exists [1,2].

What’s needed is an accurate and precise formula, based on personal bone structure and height, that gives the maximum lean body mass a trainee can achieve without the use of anabolic drugs. The material in this article is based on an except from the e-book Your Muscular Potential: How to Predict Your Maximum Muscular Bodyweight and Measurements – specifically, the sections dealing with the accomplishments of drug-free bodybuilding champions of the past and present. If you accomplish the predictions outlined below you’ll have developed a body proportional and equally developed to theirs.
Predicting Maximum Muscular Bodyweight

The amount of lean body mass a human body can develop and maintain is limited by it’s own, naturally occuring, hormone levels. A fundamental reason as to why males carry more lean body mass than females, and have the potential to develop greater amounts of muscle in less time, is precisely because their natural testosterone levels are many times higher than females. Testosterone is required for muscle growth and maintenance, and there is a limit as to the amount of testosterone the male body can produce in good health. Resistance training results in micro-trauma to protein structures within the muscle cells and circulating testosterone is instrumental in the repair and replacement of these structures. Once the body has attained the maximum amount of muscle mass that the available testosterone can maintain – i.e. “repair” after training and replace with an equal amount of “new” proteins – then no additional proteins, and therefore no additional muscle mass, can be added and maintained. It is a fundamental and irrefutable fact, though one which the bodybuilding and supplement industries, and their deluded followers, routinely ignore (a completely unsupportable position, but “defended” quite vehemently nonetheless). The normal adult male serum testosterone level for a man under 40 years of age is between 3 and 10 ng/ml, and decreases with increasing age [8-10]. This clearly imposes a personal limit on the amount of lean body mass that can be developed and maintained without the use of exogenous anabolic drugs (i.e. “steroids”), and any further development beyond this point will require drug-use. Other major factors influencing ultimate muscular potential are muscle belly lengths, fast-twitch to slow-twitch fiber ratio, etc.

So there will be variations in potential between people even of identical bone structures. Consequently, no equation predicting maximum muscular bodyweight will be 100% accurate for everybody. What such an equation can do, however, is establish an upper limit of potential based on the achievements of drug-free bodybuilding champions. These men possess naturally high testosterone levels, full muscle bellies, and the host of structural characteristics that permit the development of world-class physiques – they reflect the upper limit of male drug-free muscular potential. Therefore, a muscular bodyweight prediction equation based on such a group of men provides an estimate as to the maximum muscular size a person of a given structure is likely to achieve without the use of anabolic drugs and while maintaining a “balanced” physique. Though, in reality, the very nature of the accomplishments of elite bodybuilding champions strongly implies that the majority of trainees will not be able to quite reach such a level.

However, if you have long muscle bellies, good health and hormone levels, a growth supporting diet and lifestyle, and train according to your needs then you should, in time, be able to approach such a predicted muscular weight. If one of these factors doesn’t apply to you then your potential will be less. It has been my experience though – based on almost ten years of data collection and analysis and owing to the fact that ultimate muscular potential is so closely tied to bone structure – that most healthy people can come surprisingly close to what such a formula can predict …if they train correctly for long enough.

One must also consider the case where a person’s bone structure tapers at the extremities. For instance, the wrist and ankle circumferences could be “small” but the shoulder and hip structures not correspondingly “small”. This trait is not entirely uncommon and can produce deceiving results. The opposite end of the spectrum is a slightly built person who has large wrists and ankles – this type of structure also exists. In these cases, it is more difficult to accurately predict muscular potential. I have chosen to present a simplified lean body mass prediction equation, but with the caveat that an adjustment be made for thinly and thickly built men whose structures are not accurately reflected in their wrist and ankle measurements.

Finally, potential lean body mass increases with body fat percentage. Research has found that very heavy Sumo wrestlers actually carry more lean body mass than bodybuilders of the same height [11]. A statistical analysis of off-season vs. contest-condition bodybuilders was performed to account for this in the lean body mass prediction equation.
Predicting Maximum Muscular Bodyweight: The Equation

Based on an analysis of some 300 class and overall title winning drug-free bodybuilders and strength athletes from 1947 to 2010 the following equation, predicting the maximum lean body mass someone of a given height and bone-structure can achieve without the use of anabolic drugs, was derived. It describes a “normal” state of nutrition and fluid retention in the trainee. (There is a link at the end of this article to an online calculator based on all of the formulae presented here).

where,
H = Height in inches
A = Ankle circumference at the smallest point
W = Wrist circumference measured on the hand side of the styloid process.
(The styloid process is the bony lump on the outside of your wrist.)
%bf = The body fat percentage at which you want to predict your maximum lean body mass

The above equation, as it was derived from collected data, applies most accurately to individuals of approximately average, balanced bone structures for their heights and average muscle belly lengths. Very thin ectomorphic men can expect to achieve roughly 95% of the lean body mass that the equation predicts. Likewise, very endo-mesomorphic men, men who have disproportionately wide hips, thick shoulder structures and torsos, high natural testosterone levels, exceptionally long muscle bellies or uncharacteristically small joints for their frame size may be able to exceed the prediction by up to roughly 5% in extreme cases (WNBF World Champion and Mr. Universe Rob Hope comes to mind).

So, using this equation, for a 5’9″ (69 inches) tall bodybuilder at 10% body fat with 7.0″ wrists and 8.7″ ankles the equation would yield:

To convert maximum lean body mass to maximum bodyweight at any given body fat, use this equation:

Body weight = (Lean body mass / (100 – %body fat) ) x 100

Using our example bodybuilder, at a lean and healthy 10% body fat his total bodyweight would be:

Body weight = (173.7 / (100 – 10) ) x 100 = 193.0 pounds

As the above equation is intended for bodybuilders in a steady, maintainable state, special adjustments should be made for “bulking” off-season bodybuilders who, due to heavy food and liquid intake, often carry additional pounds of “lean body mass” in the form of fluid retention, labile proteins and contents in the digestive tract. In these cases, a bodybuilder may carry up to 4% additional body weight due to these factors – the predicted body weight must be multiplied by a maximum factor of 1.04 to account for this. Using our example trainee to illustrate his weight in a maximally “bulked” state, we get:

Maximum Bulked Body weight = 193.0 x 1.04 = 200.7 pounds

It must be kept in mind, however, that within days of reducing food intake back down to maintenance levels or below, this “transitory” lean body mass will quickly be lost and the trainee’s weight will return more in line with the “Maximum lean body mass” equation. Most trainees, in fact, have experienced such temporary “swells” in body weight. For instance, a Sunday night of eating peanuts and drinking beer, or just a day of heavy eating, can show up as five or more additional pounds on the scale come Monday morning – that will not last, however, as the retention will be “shed” over the following days after resuming a more normal diet. It is not dissimilar to the weight fluctuations experienced by anyone following a carbohydrate cycling diet.

The body weight prediction formula was developed as an amalgamation of data from past and present drug-free bodybuilding champions and anthropometrics data from the U.S. Army, Navy, and several anthropometrics studies done by various organizations throughout the world (for ergonomic designs, etc.). In addition, a comparison was made with the fat-free mass indexes of champion bodybuilders, as presented in the work of Dr. E. M. Kouri, et. al. A mathematical regression was then done to obtain fits based on the heights, wrist sizes and ankle sizes of elite-level drug-free bodybuilding competitors. This regression was then converted to an equation consistent with the well-verified weight-to-height2 relation.

Table 1 presents a list of drug-free bodybuilding champions both past and present [3-6,12,13] with their actual weights and the weights predicted by the formulae. Also included are the maximum “bulked” off-season body weights of these bodybuilders (or after a day or few of heavy eating) and the percent body fats used in the predictions. The current champions are unnamed because several have expressed to me personally that they did not want their stats published publicly (there is a “sensitive” nature to the body weights and measurements of actively competing bodybuilders).

As can be seen from the data, the predictions are, in fact, quite accurate. As well, these bodybuilders were chosen to represent as broad a group of elite competitors as possible – with dates ranging from 1947 to 2010 and bodybuilders of different heights, bone structures and leanness being deliberately selected.

Comparing these body weights to population averages shows that these champions carry 24-26% more lean body mass than the average person of their height and bone structure. A large man such as Reg Park would carry 38-41 pounds more muscle than his average, non-weight training counterpart. A smaller structured man, such as 2006 WNBF World Champion Jon Harris, would carry about 31-34 pounds more muscle than an average, non-weight training man of his height and structure. It is also interesting to note that the absolute level of muscle mass carried by modern drug-tested bodybuilders is not statistically greater than that carried by bodybuilders from the pre-drug era – though modern bodybuilders compete at much lower body fat levels.

If you are lifetime drug-free and have approximately average bone structure girths for your height, use this formula (and bulked adjustment) to set a realistic and accurate bodyweight goal for yourself (individuals with significantly smaller or larger than average bone structures for their heights are more accurately treated in the e-book Your Muscular Potential: How to Predict Your Maximum Muscular Bodyweight and Measurements). In any case, if you achieve the prediction you’ll be carrying as much muscle, with respect to your frame size, as an elite-level natural bodybuilder.

A Note Concerning Body Fat Estimation Methods: Common body fat estimation methods such as equations and charts based on skin-folds notoriously underestimate body fat levels in heavily-muscled individuals. This error can be up to roughly 4%. What that means is when you see an obviously smooth off-season bodybuilder claiming that skin-folds show he is only 10% body fat, the reality is he’s more likely closer to 14%. Keep this in mind if you are an advanced bodybuilder using skin-folds to estimate your own body fat percentage or when considering bodybuilders’ seemingly routine claims of contest conditions of less than 4% body fat. I used the published research plus personal experience with hydrostatic weighing to adjust the body weight prediction formula accordingly.
Predicting Maximum Muscular Measurements

There have been several sets of equations presented over the years that attempt to predict maximum muscular measurements based on height or wrist size. The problem is they typically don’t consider both, and very few of them consider the lower body structure. Along with several efforts by David P. Willoughby [3-5], a popular set of formulae was presented by bodybuilding author John McCallum in the mid-1960s [14]. McCallum’s guidelines were based on wrist size, without the lifter’s height taken into consideration. Such an approach can be sufficiently accurate for a lifter of average stature but muscular potential is, to a degree, influenced by height. For instance, a 6’1″ tall trainee with an 8″ wrist will, generally, have the potential to develop larger muscular measurements than a 5’8″ trainee with an 8″ wrist. For maximum accuracy, height must be considered when making such predictions.

The statistical analysis of the anthropometric measurements of roughly 300 drug-free class-winning and overall title winning bodybuilders and muscularly large strength athletes from 1947 to 2007 resulted in strong-to-moderate correlations between height, wrist girths, ankle girths and muscular measurements. Moreover, as the absolute muscular development of these elite-level athletes has not significantly changed over this 60-year period, genetic upper limits become apparent, and any inferences drawn from this group can be applied to future potential as well. Based on clear correlations, athletes noted for outstanding body part development were selected on a per body part basis, and bodybuilders with weaknesses in these areas were omitted from the data pool. The following correlations were found: